Most books on data structures assume an imperative language such as C or C++. However, data structures for these languages do not always translate well to functional languages such as Standard ML, Haskell, or Scheme. This book describes data structures from the point of view of functional languages, with examples, and presents design techniques that allow programmers to develop their own functional data structures. The author includes both classical data structures, such as red-black trees and binomial queues, and a host of new data structures developed exclusively for functional languages. All source code is given in Standard ML and Haskell, and most of the programs are easily adaptable to other functional languages. This handy reference for professional programmers working with functional languages can also be used as a tutorial or for self-study.

"This book is important because it presents data structures from the point of view of functional languages...a handy reference for professional functional programmers...Most of the programs can easily be adapted to other functional languages. Even C and Java programmers should find implementing these data structures a relatively straightforward process...Programs are physically well structured and readable, and are displayed in boxes. Okasaki has produced a valuable book about functional programming, exploring a wide range of data structures...a significant contribution to the computer science literature." Computing Reviews